Preheat the oven to 350 F and line an 8x8" baking pan with parchment paper. Spray with avocado oil spray and set aside.
Using a saucepan, combine the apple-filling ingredients and set over medium-low heat. Stir to combine and simmer for 5-8 minutes (stirring often) or until the apples soften. Set aside.
For the crust, combine the dry ingredients and mix until well incorporated. Stir in the wet ingredients and stir until the dough is fully combined.
Using the prepped baking pan, flatten the majority of the crust onto the bottom of the pan until it's evenly thin. You'll save about 4 tbsp of the crust dough for the topping.
Par-bake the crust in the oven for 8 minutes. Remove from the oven and allow to cool for 5 minutes.
Layer the apple filling on top of the crust and evenly distribute. Crumble the remainder of the crust topping over the apples and slightly flatten it.
Bake the bars in the oven for another 25-30 minutes or until the crust topping is golden brown. Remove from the oven and allow to cool for about 5 minutes before carefully removing from the pan. Allow to cool further and slice into 9 bars. Top with optional caramel sauce (below) if desired.